St Helens forward Shaun Magennis has announced his retirement from the game after failing to shake off a persistent knee injury.

The 23-year-old made 33 appearances for the club after joining them from local amateur club Blackbrook in 2008.

"My knee has been bad for a few years now, since I was 17 really," he said. "It was getting worse and worse and I kept having surgery on it.

"It came to a point last year when I couldn't train fully and I stopped looking forward to training as my knee was that sore.

"I spoke to my surgeon and he said he could do an operation so I could get on with the rest of my life. In the end I chose that and now I have to move on."

St Helens general manager Mike Rush, who selected Magennis nine times last season when he was caretaker coach, said: "We are all upset that Shaun has had to retire from the sport.

"He has shown great mental toughness to come back from a number of injuries but sadly this latest one is one step too far.

"We will continue to rehabilitate Shaun and offer as much support as we can as he looks to take up the next challenge in his life."

Magennis' last Super League appearance was against Wigan in a 42-16 defeat at the Magic Weekend in May, when he was one of three players sent off for punching and was subsequently handed a three-match ban.